William Poole (February 24, 1821 – March 8, 1855), also known as Bill the Butcher and Bill the Butcher Poole, was the founder of the street gang the Bowery Boys and a leader of the Know Nothing political movement in mid-19th century New York City.

Poole was born in Sussex County, New Jersey to parents of English descent.[1] In 1832, his family moved to New York City to open a butcher shop in Washington Market, Manhattan. Poole trained in his father's trade and eventually took over the family store. In the 1840s, he worked with the Howard (Red Rover) Volunteer Fire Engine Company #34, on Hudson and Christopher Streets, and started the Washington Street Gang.

As a well-known gang leader and pugilist, Poole was frequently involved in fights, brawls, and other confrontations. The New York Daily Times reported the following on October 23, 1851:

A Brutal Outrage in Broadway. We learn that at an early hour yesterday morning, two noted pugilists entered Florence's Hotel, corner of Broadway and Howard street, and without any provocation seized the bar-keeper and beat his face to a jelly. It appears that Thomas Hyer, William Poole, and several others entered the above hotel, and while one of the party held Charles Owens (the bar-keeper) by the hair of his head, another of the gang beat him in the face to such an extent that his left eye was completely ruined and the flesh of his cheek mangled in the most shocking manner. After thus accomplishing the heartless act, all of them made an effort to find Mr. John Florence, the proprietor of the hotel, with a view of serving him in the same manner, but not succeeding in their latter design, they found the hat of Mr. Florence and wantonly cut it into strips, and trampled it under their feet. The desperadoes then left the house, and in the meantime Mr. Owens was placed under medical attendance, and in the course of a short time he proceeded to the Jefferson Market Police, in company with Mr. Florence, where they made their affidavits respecting the inhuman outrage, upon which Justice Blakeley issued his warrants for Hyer, Poole, and such of the others who were concerned in the affair, and the same were placed in the hands of officer Baldwin for service. Since the above was written we have been reliably informed that the affray originated from the fact of the barkeeper having refused them drinks, after they had been furnished with them twice in succession.

Poole's archrival, John Morrissey, was an Irish immigrant and an enforcer for Tammany Hall. Morrissey was also a popular boxer and challenged Poole to a match. Though the two men were of differing ethnic backgrounds and political parties, the initial grounds for their dispute may have arisen from an earlier bet by Poole on a boxing match at Boston Corners on October 12, 1853, in which Poole had placed his bet on Morrissey's opponent, "Yankee Sullivan".

The results of the boxing match were disputed, and Poole was against Morrissey being paid.

Morrissey plotted revenge and on February 25, 1855, Lew Baker and Jim Turner, friends of Morrissey, shot Poole dead, at Stanwix Hall, a bar on Broadway near Prince, at that time a center of the city's nightlife. The New York Daily Times reported on February 26, 1855 the following:

Terrible Shooting Affray in Broadway – Bill Poole Fatally Wounded – The Morrissey and Poole Feud – Renewal of Hostilities – Several Persons Severely Wounded. Broadway, in the vicinity of Prince and Houston Streets, was the scene of an exciting shooting affair about 1 o'clock yesterday morning, which is but a repetition of a similar occurrence that transpired a few weeks ago under Wallack's Theatre between Tom Hyer, Lewis Baker, Jim Turner and several other noted pugilists... William Poole was buried in Green-Wood Cemetery, Brooklyn, Kings County, New York.

Poole died from the gunshot wound on March 8, 1855 in his home on Christopher Street, leaving a wife and a son named Charles Poole. The feud had been very public, and the New York Times covered the events of Stanwix Hall almost every day for a month. A local newsman reported Poole's last words were, "Good-bye boys; I die a true American." He was buried on March 11, 1855, in Brooklyn's Green-Wood Cemetery in an unmarked grave. A tombstone was added in 2004; the grave is number 48 and 49, F/G 6(v).

Lewis Baker quickly fled New York, taking the brig Isabella Jewett, which was headed for the Canary Islands. George Law, Sr. furnished the clipper ship Grapeshot to pursue Baker. It intercepted the Jewett on April 17, 1855, and Baker was captured. He was tried three times for the murder of Poole but all three trials ended in a hung jury. Morrissey went on to open up several bars and accumulated $1.5 million, but was never accepted by American aristocracy. He later served as a state senator and died of pneumonia in 1878.